Window security lock

1. A window security lock comprising:

a housing, said housing defining an elongated slot and an L-shaped slot, a pair of posts, said posts mounted on said housing, a stop, said stop slidably mounted within said housing, said housing defining a first indent, a second indent, said housing first indent extending into said housing elongated slot, said housing second indent extending into said housing L-shaped slot, a cover, said cover defining an elongated slot and an L-shaped slot, said cover defining a first indent, a second indent, said cover first indent extending into said cover elongated slot, said cover second indent extending into said cover L-shaped slot, said cover contiguous said housing for maintaining said stop therebetween, said stop comprising a body, said body defining a pair of chamfered surfaces, a first pin, said first pin attached to said stop and positioned in said housing elongated slot and in said cover elongated slot, a second pin, said second pin attached to said stop and positioned in said housing L-shaped slot and in said cover L-shaped slot, a lip, said lip attached to said body, a resilient member, said resilient member contiguous said stop, said lip for engaging said housing when said stop is pivoted outwardly therefrom while said chamfered surfaces engage said housing, said resilient member angularly contained between said posts whereby said resilient member is freely rotatable from one angular position toward an opposed annular position as said stop pivots, said resilient member comprising a coil spring.

2. The window security lock of claim 1 further comprising a rigid fixed finger, said fixed finger attached to said housing for engaging a window frame.

3. The window security lock of claim 2 further comprising a flexible finger, said flexible finger attached to said housing in opposing relation to said fixed finger for engaging a window frame.

4. The window security lock of claim 1 wherein said stop defines a spring slot, said resilient member residing within said spring slot.

5. The window security lock of claim 4 wherein said spring slot is triangularly shaped.

6. The window security lock of claim 1 wherein said housing defines a stop opening, said stop opening to allow said stop to pivot from said housing.

7. The window security lock of claim 6 wherein said lip will obstruct said stop opening when said stop extends from said housing.

8. A security lock mountable in the upper sash jamb of a double hung window, the lock openable to prevent ascension of the lower sash by engagement with the header of the lower sash and closable to permit ascension of the lower sash, the lock comprising:

a housing, said housing defining an elongated slot and an L-shaped slot, said housing elongated slot and said housing L-shaped slot each defining an indent, a cover, said cover attached to said housing, said cover defining an elongated slot and an L-shaped slot, said cover elongated slot and said cover L-shaped slot each defining an indent, said housing elongated slot coincidental with said cover elongated slot, said housing L-shaped slot coincidental with said cover L-shaped slot; and

a pivotable stop, a pair of pivot pins, said stop fixed to said pivot pins, said pivot pins positioned to slide within said elongated slots and said L-shaped slots of both said cover and said housing simultaneously and all of said indents for preventing inadvertent operation of said stop, said stop defining a pair of chamfered surfaces engaging interior surfaces of said housing, a lip, said lip for reducing debris and insect entry when the lock is open, a coil spring, said stop defining a spring slot, a pair of posts, said pair of posts attached to said housing, said coil spring having one end contained in said spring slot and the opposite end maintained by said pair of posts, positioning the coil spring at an angle, whereby said coil spring is rotatable from one angular position toward an opposed angular position as said stop pivots.

9. The security lock of claim 8 wherein said stop further comprises ridges, said housing comprising a face, said ridges recessed behind said housing face when the lock is closed for avoiding a sash header seal on the lower sash.

10. The security lock of claim 8 wherein said L-shaped slots are below said elongated slots and the bottom of said stop slides outwardly to prevent ascension of the lower sash.

11. The security lock of claim 8 wherein said spring slot is triangularly shaped.